Joint assembly comprising a deforming element

ABSTRACT

PCT No. PCT/CA96/00649 Sec. 371 Date Jul. 20, 1998 Sec. 102(e) Date Jul. 20, 1998 PCT Filed Sep. 26, 1996 PCT Pub. No. WO97/11755 PCT Pub. Date Apr. 3, 1997The invention relates to an improved joint assembly comprising a deforming element that is compressed to secure a first member into the recess of a second member. Preferably the deforming element comprises angular projections and is made from a relatively soft material which allows for its deformation. The joint of the invention has the advantage of not requiring any heat or tool and is particularly useful for attaching a hockey stick blade to a hockey stick handle without the need of adhesives or other types of mechanical connectors. The invention also relates to a hockey stick blade and to a hockey stick incorporating the deforming element of the present invention.

This application claims the benefit of U.S. Provisional Application No.60/004,319 filed Sep. 26, 1995.

FIELD OF THE INVENTION

The present invention relates to an improved joint assembly comprising adeforming element that is particularly useful for attaching a hockeystick blade to a hockey stick handle. The invention also relates to ahockey stick blade and to a hockey stick incorporating the jointassembly of the present invention.

BACKGROUND TO THE INVENTION

For quite some time, manufacturers of hockey equipment have beenoffering alternatives to the traditional wooden stick by offering hockeysticks in which the blade and the handle are separate components thatmay be secured to one another by the player. These sticks commonlycomprise a blade, made from traditional materials such as wood,reinforced with carbon fibres or glass fibres, and a shaft commonly madefrom aluminium. These sticks have the advantages of exhibiting therequired amount of stiffness while keeping the "wood-like" feel to whichthe players are accustomed. Since the failure of a stick usually occursat the blade, such hockey sticks are also relatively cheaper to own inthe long run since, upon breakage, the player only has to replace thewooden blade that can be purchased at a lower price than a completewooden stick.

Another advantage to having removable blades is that the player iscapable of adapting his stick to the surface of play. This has beenparticularly advantageous in recent years with the advent of in-lineroller skates and roller hockey. Since roller hockey is played on asurface which is harsher than ice, a player practising such sportrequires a blade whose abrasion and wear properties differ fromtraditional ice hockey blades. Removable blades thus allow a player tokeep his or her favourite handle and simply replace the blade toaccommodate the different surfaces of play.

In order to secure a hockey blade to a hockey stick, many manufacturersare providing replacement blades comprising hot-melt adhesives or otherthermo bonding materials. To replace the blade, the player, or theperson responsible for the player's equipment, must first heat theportion of the handle that is adapted to receive the blade so as tosoften or melt the adhesive thereby permitting the removal of the oldblade which can then be discarded. The new blade is then inserted inplace in the handle and the joint heated again. The blade/handlecombination is then left to cool down to permit the adhesive to set. Thetype of appliance commonly used to provide the required amount of heatrange from the common household hair dryer to the more powerful andfaster hot air guns and torches, the latter ones being preferred becauseof their capacity to quickly generate the necessary amount of heat.

Apart from the inherent danger associated with fire, these types ofjoints possess many disadvantages including the necessity to carryadditional equipment such as a hair dryer or a torch. Another importantinconvenient is that these types of joints are not adapted to be usedwith sticks made from materials other than metal. Indeed, hockey stickhandles made from composite materials have limited heat tolerance andmay structurally deteriorate in the area of the joint when subjected toheat.

In view of this, other manufacturers have suggested using various typesof mechanical connectors such as locking pins or screws. However, thesetypes of joints also have various disadvantages, including the necessityof carrying the required tools. Another important disadvantage is thatapertures must usually be performed across the handle to receive thesescrews or pins. Such apertures may weaken the structural integrity ofthe handle and increase the manufacturing costs of the stick.

OBJECTS AND STATEMENT OF THE INVENTION

It is therefore an object of the present invention to provide a jointassembly particularly useful for use with a sport stick.

It is a further object of the invention to provide a removable hockeystick blade that may be retrofitted to conventional hockey stickhandles.

It is a further object of the present invention to provide a hockeystick comprising a removable blade which does not require any heating ortools to be assembled or disassembled with the handle.

As embodied and broadly described herein, the invention provides asporting implement including:

a first member;

a second member;

a joint removably securing said first member to said second member, saidjoint including:

a recess formed on one of said members;

a projection formed on the other of said members, said projection beingcapable of being received in said recess;

a fastener between said projection and an inner wall of said recess,said fastener being resiliently deformable upon insertion of saidprojection in said recess and being capable of establishing in responseto the resilient deformation a condition of frictional lock between saidprojection and an inner wall of said recess.

For the purposes of this specification the expression "resilientlydeformable" refers to the ability of a body to recover its size andform, at least partially, following deformation. This definition doesnot imply that the body must recover fully to its original shape andsize when the deformation effort is removed. Rather, the definitionintends to specifically encompass situations where the shape and sizerecovery its only partial. Also, the expression "frictional lock" refersto a condition in which the fastener generates sufficient frictionalforce against the inner wall of the recess, the projection or both, toprevent or at least substantially reduce the likelihood of separation ofthe joint under normal efforts encountered when the sporting implementis being used.

In a preferred embodiment, the sporting implement is a hockey stick, thenovel joint being used for securing a blade member provided with theprojection to a handle member having the recess in which the projectionis inserted. The fastener comprises a resilient block having at leastone protuberance, such as a tooth extending angularly away from thedirection of insertion of the projection into the recess. This featuredonates to the fastener an unidirectional locking capability that ismanifested when one attempts to remove the projection from the recess.When the projection is inserted in the recess the tooth-likeprotuberance yields away thus permitting to assemble the joint byapplying reasonable compressive force. However, when one attempts toseparate the joint the frictional force generated against the surface ofthe toot-like protuberance acts in a way to further wedge it between theprojection and the recess wall, thus resisting separation. In a mostpreferred embodiment, the fastener is permanently attached to the blademember.

As embodied and broadly described herein, the invention also provides ahockey stick blade comprising a shaft portion for insertion into arecess of a hockey stick handle, said shaft portion including afastener, said fastener being resiliently deformable upon insertion ofsaid shaft portion in the recess and being capable of establishing inresponse to the resilient deformation a condition of frictional lockbetween said projection and an inner wall of said recess.

In yet another embodiment, the invention provides a hockey stickcomprising:

a handle having a first end and a second end, said handle including arecess at said first end;

a blade comprising a shaft portion for insertion into said recess;

a fastener between said shaft portion and an inner wall of said recess,said fastener being resiliently deformable upon insertion of said shaftportion in said recess and being capable of establishing in response tothe resilient deformation a condition of frictional lock between saidshaft portion and an inner wall of said recess.

In a preferred embodiment, the shaft portion is generally rectangularand the fastener includes a pair of resilient blocks mounted on oppositesides of the shaft portion. Most preferably, the resilient block has adurometer hardness less than about 73A and includes three tooth-likeprotuberances extending angularly in a direction away from the directionof insertion of the blade into the handle. Other preferred featuresinclude providing a resilient block having an offset of at least 1.0 mm(0.04 inch) from the walls of the shaft and tooth-like protuberancesthat extends at an angle of approximately 60°.

As embodied and broadly described herein the invention further providesa fastener for securing a hockey stick blade member to a hockey handleblade member, one of the members including a recess and the other of themembers including a projection capable of insertion in the recess, saidfastener being resiliently deformable upon insertion of the projectionin the recess and being capable of establishing in response to theresilient deformation a condition of frictional lock between theprojection and an inner wall of the recess.

Other objects and features of the invention will become apparent byreference to the following specification and to the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The following is a description by way of a preferred embodiment,reference being made to the following drawings, in which:

FIG. 1 is a perspective view illustrating a portion of a handle and ahockey stick blade comprising a joint assembly according to the presentinvention;

FIG. 2 is an enlarged side elevational view illustrating a portion of ashaft formed on the hockey stick blade, comprising a friction fasteneraccording to the invention;

FIG. 3 is a further enlarged side elevational view of the frictionfastener according to the invention;

FIG. 4 is a fragmentary view of a hockey stick blade with the frictionfastener according to the present invention, illustrating the insertionof the blade in the handle performed to assemble the hockey stick;

FIG. 4a is a fragmentary further enlarged view of the hockey stick bladewith the friction fastener according to the present invention,illustrating the resilient deformation to which the fastener issubjected when the blade is inserted into the handle;

FIG. 5 is a fragmentary view of a hockey stick blade with the frictionfastener according to the present invention, illustrating the removal ofthe blade from the handle;

FIG. 5a is a fragmentary further enlarged view of the hockey stick bladewith the friction fastener according to the present invention,illustrating the wedging effect on the fastener tooth-like protuberancesthat occurs when the blade is removed from the handle;

FIGS. 6 to 9 are side elevational views illustrating variants of thefriction fastener according to the present invention; and

FIG. 9a is an exploded view of the embodiment of the friction fastenerillustrated at FIG. 9.

DESCRIPTION OF A PREFERRED EMBODIMENT

Referring to FIG. 1, there is shown a hockey stick comprising anelongated handle 2 and a blade generally referred to at 10.

The handle 2 may be made from a metallic material such as aluminium ormay be manufactured from a variety of composite materials such as carbonfibres, glass fibres, Kevlar or the like. It is preferably ofrectangular shape or may comprise convex and concave side walls toimprove the grip of the player. Since it does not require any heating,the joint assembly of the present invention may be used with many typesof hockey stick handle including ones made from composite material andis therefore not limited to any particular type of handle. The onlystructural requirement of the handle is that it comprises a recess 3(FIG. 4) at one end thereof for receiving a shaft portion 6 of the blade10.

The blade 10 comprises a bottom edge 4 for contacting a surface of playand also comprises a shaft portion 6 preferably having a generallyrectangular cross section comprising a front wall 8, a rear wall 12 andwider side walls 14. In the preferred embodiment, the front and rearwalls 8, 12 are approximately 15.5 to 15.7 mm (0.612 to 0.617 inch) widewhile the side walls 14 are approximately 25.9 to 26.0 mm (1.023 to1.027 inch) wide. The shaft portion 6 has a length of approximately 76.2mm (3 inches).

The shaft portion 6 of the blade closely conforms with the shape of therecess 3 so that there is little free play once the shaft portion of theblade is inserted into the recess 3. The blade also preferably comprisesa shoulder 16 that will abut against the end portion of the handle 17upon telescopic engagement of the blade into the recess 3 as describedhereinafter. Furthermore, the dimensions of the shaft portion and of theblade are such that the outside walls of the blade will be flush withthe outside walls of the handle when the shaft portion is inserted intothe recess.

As shown more particularly in FIG. 3, the shaft portion 6 comprises afriction fastener including at least one resilient block 20 having aplurality of tooth-like protuberances 22 that extend angularly in adirection away from the direction of insertion of the shaft portion 6into the recess 3(the direction of insertion is shown by the arrow inFIG. 4). In the preferred embodiment, the angle θ of each tooth-likeprotuberance is approximately 60° although it may vary as describedhereinafter. In order to detachably secure the blade to the handle, thetooth-like protuberances 22 of the resilient block 20 extend beyond theplane of the walls of the shaft portion. In the preferred embodiment,the projection height x' of the tooth-like protuberances, is of at least1.0 mm (0.04 inch). In the most preferred embodiment, the resilientblock is approximately 16.7 mm (0.660 inch) long but the length may varyto suit the player's preference. The desired projection height isarrived at by forming on the surface of the shaft portion 6 on which theresilient block is placed a recess 30 whose depth determines the valuex'.

Referring now to FIG. 4, in order to detachably secure the blade 10 tothe stick handle 2, the user simply inserts the shaft portion 6 into therecess 3 of the handle and exerts the required amount of force until theshaft portion is completely inserted into the handle, i.e. until theshoulder 16 abuts against the end portion 17 of the handle. As shownmore particularly in FIG. 4a, during insertion of the blade, thetooth-like protuberances 22 of the deforming element 20 will resilientlydeform and yield inwardly ("inwardly" means toward the shaft portion 6)and be compressed against the inner wall of the handle. The angularorientation of the tooth-like protuberances will facilitate their inwardyielding and as a result, the amount of force required to insert theblade into the handle will be substantially less than the amount offorce required to remove it.

Because the block 20 is made of resilient material, once inserted in therecess 3, the tooth-like protuberances 22 will generate contact frictionagainst the inner wall of the recess 3 and will prevent the blade fromdisengaging from the handle. As shown in FIG. 5, when the user desiresto remove the blade, he or she will simply pull on the blade or thehandle in a direction opposite the direction of insertion. However, asshown more particularly in FIG. 5a, because of the angular orientationof the projections, they will have a tendency to roll back and wedgethemselves between the inner wall of the recess 3 and the shaft portion6, thus resisting removal. The amount of force required to remove theblade will thus be significantly greater than the amount of forcerequired to insert the blade. In a preferred embodiment, the deformingelement will be configured so a to provide a removal load ofapproximately 25 to 35 kg.

EXAMPLES

The following examples have been tested and have provided satisfactoryresults. The examples used are as illustrated in FIG. 2 and consist of ablade having a shaft portion comprising a friction fastener thatincludes two resilient blocks, each block being approximately 16.7 mm(0.660 inch) long, bonded to the uppermost portion of each of the frontand rear walls 8 and 12. Each resilient block comprises three tooth-likeprotuberances extending at an angle of approximately 60°. The resilientblock is made from polyurethane having a durometer hardness ofapproximately 73A when measured in accordance with the ASTM D-2240 test.The tested blade were inserted into the handle of a Bauer® Ergo™ stickhaving an internal dimension of 15.65±0.05×25.98±0.05 mm(0.616±0.002×1.023±0.002 inches).

    ______________________________________                                             shaft                                                                         dimension-                                                                              shaft              Maximum                                                                              Plateau                                   front or  dimension- offset × 2                                                                      tensile                                                                              tensile                                   rear wall mm                                                                            side wall  mm      load   load                                 Ex.  (inches).sup.1                                                                          mm (inches).sup.1                                                                        (inches).sup.1                                                                        (kg).sup.2                                                                           (kg).sup.3                           ______________________________________                                        1    15,49 (.610)                                                                            26,04 (1.025)                                                                            2,67 (.105)                                                                           25     19                                   2    15,49 (.610)                                                                            26,04 (1.025)                                                                            2,77 (.109)                                                                           36     28                                   3    15,49 (.610)                                                                            26,04 (1.025)                                                                            2,87 (.113)                                                                           39     30                                   4    15,49 (.610)                                                                            26,04 (1.025)                                                                            1,91 (.075)                                                                           29     23                                   5    15,49 (.610)                                                                            26,09 (1.027)                                                                            1,91 (.075)                                                                           35     29                                   6    15,54 (.612)                                                                            25,98 (1.023)                                                                            1,91 (.075)                                                                           34     30                                   7    15,62 (.615)                                                                            25,98 (1.023)                                                                            1,91 (.075)                                                                           40     32                                   8    15,62 (.615)                                                                            26,04 (1.025)                                                                            1,35 (.053)                                                                           34     21                                   9    15,62 (.615)                                                                            26,04 (1.025)                                                                            1,52 (.060)                                                                           35     22                                   10   15,62 (.615)                                                                            26,04 (1.025)                                                                            1,73 (.068)                                                                           46     28                                   11   15,62 (.615)                                                                            26,04 (1.025)                                                                            1,91 (.075)                                                                           49     33                                   12   15,62 (.615)                                                                            26,09 (1.027)                                                                            1,91 (.075)                                                                           50     35                                   ______________________________________                                         .sup.1 The dimensions were all measured in inches and later converted int     mm based on the following equation (1 inch = 25,4 mm).                        .sup.2 The maximum tensile load may be defined as the maximal force           required to remove the blade from the handle, this maximum force usually      occurring during the initial effort. It was recorded using a dynamometer.     .sup.3 The plateau tensile load may be defined as the average or constant     force required to remove the blade from the handle. It was also recorded      using a dynamometer.                                                          While some of the shaft dimension listed are larger than the actual           internal dimension of the handle, an expansion of the latter compensates      for any difference in size.                                              

The purpose of the conducted test was to determine the parametersrequired to provide a removal load, i.e. the force required to removethe blade, of between 25 to 35 kg.

The sticks described above all provided satisfactory results, namely asuitable removal force and no free play of the shaft within the recess.

Other materials having different properties could of course be used toaccommodate the conditions of play and the users' preferences. Forexample, the resilient block used in an ice hocky blade which normallyis subjected to sub-zero temperatures may not require the same hardnessas one used by a roller hockey player in a warm environment. Similarly,a younger player that isn't physically very strong may not require thesame type of blade and removal load as the professional player. All thevarious parameters that may affect strength of the joint assembly,including the type and hardness of the material, the offset, the angleand the amount of tooth-like protuberances, and the size of theresilient block may be modified to take into consideration these variousconditions.

For example, the type of material used is not restricted to polyurethanebut may comprise any type of resilient material capable of providing asatisfactory joint. These types of materials may be determined byroutine testing. Furthermore, in a less preferred embodiment, theresilient block could be made from a material that would allow theprojections to deform and be compressed enough to secure the blade tothe handle but that would structurally fail upon removal of the blade.Such a type of sacrificial friction fastener would be satisfactory forblades that need to be discarded after a single removal.

With regard to the offset (value x'), it will vary depending on the sizeof the shaft portion relative to the recess of the handle and will alsodepend upon the amount of free play present in the joint assembly, theobject being to keep the free play at a minimum. Thus, as shown by theabove described examples, a smaller shaft, such as example 1, willaccommodate a higher offset than a larger shaft, such as example 9, andwill require a similar removal load. Similarly, shafts of identicaldimensions with offsets of different values will exhibit differentremoval loads, the higher offset requiring the biggest removal load(compare example 1 with examples 2 and 3).

The angle of the tooth-like protuberances may also be modified to changethe amount of force required to insert the blade compared with theamount of force required to remove it (removal load). The preferredembodiments described herein have the advantage of providing a jointassembly whereby the amount of force required to insert the blade issmaller than the amount of force required to remove same. However, it ispossible to conceive a joint assembly that does not comprise anytooth-like protuberances or that comprise tooth-like protuberancesextending at an angle of 90° so that the force required to insert theblade will be approximately the same as the force required to remove it.Although not optimal, such an embodiment is possible.

The number of tooth-like protuberances could also be modified to achievethe desired removal load. In test conducted using the examples describedabove, it has been found that the removal of a tooth-like protuberancedecreases the removal force by approximately 10%.

FIGS. 6 to 9a illustrate other embodiments of the invention. As shown inFIG. 6, the resilient blocks 20a may be located at an area other thanthe uppermost portion of the shaft or may not be opposite one another asshown at 20b in FIG. 7. Referring now more specifically to FIGS. 8 and9, there is shown embodiments in which resilient blocks are provided onthree of the walls of the shaft, such as on the front and rear walls andon a side wall (see 20c in FIG. 8) or on each of the side walls and onthe front or rear wall (see 20d in FIG. 9). Other combinations arepossible including the possibility of providing a resilient block oneach of the walls of the shaft portion. FIG. 9a shows yet anotherembodiment in which the resilient block 20e is not bonded to the shaftbut is slidingly received on same. More specifically, the resilientblock is made as a U-shaped part, the tooth-like protuberances beingcontinuous and extending on all three walls of the U-shaped part. Therecess formed by the U-shaped part is configured to receive a narrowedsegment of the shaft like portion 6, both components being retained toone another by friction. This embodiment allows the resilient block tobe removed easily and replaced by a fresh one.

In another embodiment, the joint assembly of the present invention couldbe used to detachably secure a grip member to the end of the handleopposite the blade receiving end. In such an embodiment, the grip membercould be provided with a deforming element according to the presentinvention and could be inserted into a recess of the handle.

The above description of the preferred embodiments should not beinterpreted in any limiting manner since variations and refinements arepossible which are within the spirit and scope of the present invention.The scope of the invention is defined in the appended claims and theirequivalents.

What is claimed is:
 1. A hockey stick comprising:a blade; a handle; anda joint removably securing said blade to said handle, said jointincluding:(a) a recess having an inner wall formed on one of said handleor said blade, (b) a projection formed on the other one of said handleor said blade, said projection adapted to be received in said recessalong a direction of insertion, and (c) a fastener disposed between saidprojection and said inner wall of said recess, said fastener having alongitudinal axis and at least one resiliently deformable tooth-likeprotuberance adapted to frictionally engage said projection to saidrecess, said at least one resiliently deformable tooth-like protuberanceextending away from the direction of insertion of said projection insaid recess and having a shape and orientation such that the requiredforce to remove said blade from said handle is greater than the requiredforce to secure said blade to said handle.
 2. The hockey stick accordingto claim 1, wherein said tooth-like protuberance is oriented at an angledifferent from 90 degrees with relation to said direction of insertion.3. The hockey stick according to claim 1, wherein said tooth-likeprotuberance is oriented at an angle of approximately 60 degrees withrelation to said direction of insertion.
 4. The hockey stick accordingto claim 1, wherein said tooth-like protuberance has a durometerhardness less than about 73A.
 5. The hockey stick according to claim 1,wherein said fastener has three tooth-like protuberances.
 6. The hockeystick as defined in claim 1 wherein said projection has a shape anddimension that closely conforms with the shape of said recess.
 7. Thehockey stick as defined in claim 1 wherein said at least one resilientlydeformable tooth-like protuberance extends beyond a plane defined bysaid inner wall of said recess.
 8. A replacement blade for a hockeystick comprising:a bottom portion adapted to contact a surface of play;a shaft portion integrally connected to said bottom portion, said shaftportion being of generally rectangular cross section and having aprojection of reduced rectangular cross section comprising a front wall,a rear wall, and wider side walls, said projection adapted to beinserted in a recess of a hockey stick handle; a shoulder defined bysaid projection and adapted to abut against an end portion of a hockeystick handle; and a fastener secured to one end of said projection, saidfastener including at least one resilient block having a plurality ofdeformable tooth-like protuberances that extend angularly towards saidbottom portion.
 9. The hockey stick blade as defined in claim 8 whereinsaid tooth-like protuberances of said at least one resilient blockextend beyond a plane defined by said walls of said projection.
 10. Thehockey stick blade as defined in claim 9 wherein said tooth-likeprotuberances are oriented at an angle of approximately 60 degrees withrelation to a longitudinal axis of said projection.
 11. The hockey stickblade as defined in claim 9 wherein said tooth-like protuberances have adurometer hardness less than about 73A.
 12. The hockey stick blade asdefined in claim 9 wherein said at least one resilient block has threetooth-like protuberances.